- For the reaction A+B⇌C+DA + B \rightleftharpoons C + DA+B⇌C+D, the expression for KcK_cKc is:
a) [A][B]/[C][D][A][B]/[C][D][A][B]/[C][D]
b) [C][D]/[A][B][C][D]/[A][B][C][D]/[A][B]
c) [A][C]/[B][D][A][C]/[B][D][A][C]/[B][D]
d) [A][D]/[B][C][A][D]/[B][C][A][D]/[B][C]
Answer: b - Which of the following is true about the equilibrium constant KcK_cKc?
a) It depends on the concentrations of reactants
b) It changes with temperature
c) It remains constant regardless of conditions
d) It equals zero at equilibrium
Answer: b - When the concentration of a reactant is increased, the equilibrium will:
a) Shift to the right
b) Shift to the left
c) Remain unchanged
d) Decrease the reaction rate
Answer: a - For a reaction at equilibrium, the reaction quotient QQQ equals:
a) Zero
b) KcK_cKc
c) Infinity
d) [A]/[B][A]/[B][A]/[B]
Answer: b - Which of the following reactions is in equilibrium?
a) 2SO2+O2⇌2SO32SO_2 + O_2 \rightleftharpoons 2SO_32SO2+O2⇌2SO3
b) 2H2+O2→2H2O2H_2 + O_2 \rightarrow 2H_2O2H2+O2→2H2O
c) N2+3H2→2NH3N_2 + 3H_2 \rightarrow 2NH_3N2+3H2→2NH3
d) C+O2→CO2C + O_2 \rightarrow CO_2C+O2→CO2
Answer: a - For an exothermic reaction, increasing the temperature will:
a) Shift the equilibrium to the right
b) Shift the equilibrium to the left
c) Have no effect on equilibrium
d) Increase the concentration of reactants
Answer: b - What is the effect of decreasing the volume of a gaseous equilibrium mixture?
a) Shifts the equilibrium to the side with more moles of gas
b) Shifts the equilibrium to the side with fewer moles of gas
c) Increases the equilibrium constant
d) Decreases the equilibrium constant
Answer: b - In a chemical reaction, equilibrium is achieved when:
a) Products are formed faster than reactants
b) Reactants are used up
c) The concentration of reactants equals products
d) The forward and reverse reaction rates are equal
Answer: d - Which of the following factors does NOT affect chemical equilibrium?
a) Concentration
b) Pressure
c) Temperature
d) Presence of a catalyst
Answer: d - For the reaction 2A⇌B+C2A \rightleftharpoons B + C2A⇌B+C, the equilibrium constant expression is:
a) [A]/[B][C][A]/[B][C][A]/[B][C]
b) [B][C]/[A]2[B][C]/[A]^2[B][C]/[A]2
c) [A]2/[B][C][A]^2/[B][C][A]2/[B][C]
d) [B][C]/[A][B][C]/[A][B][C]/[A]
Answer: b
